It has been well accepted that molecular profiling in tumor precursor lesions is fundamental to understand the molecular etiology in tumor development and to provide the potential biomarkers for early detection and prevention. Furthermore, the need to detect weak indications or small but biologically important changes in protein expression profiles remains, as cancer researchers explore the initial steps in biological-signaling cascades and compensatory processes. However, in the absence of PCR-like protein amplification, comprehensive and quantitative analysis of protein expression within 102-103 tumor cells (corresponding to a total protein content of 10-100 ng) microdissected from very tiny precursor lesions such as tubal intraepithelial carcinoma represents a daunting task which necessitates highly sensitive analytical approaches, exceeding the dynamic range of currently available proteomic platforms. Thus, the proposed research aims to develop and demonstrate an effective discovery-based nanoproteomic platform, which enables ultrasensitive and comprehensive studies of protein profiles that will have diagnostic and therapeutic relevance.